“Arareishi” (aragonite) is a mineral composed of calcium carbonate, and its composition is the same as limestone (calcite), which is the primary raw material of cement. It occurs near gypsum deposits and is prized as an ornamental object due to its unique shape. The Matsushiro Mine produced gypsum from the Meiji era to the 1960s, and the aragonite that was extracted here is unique in its shape and size, the likes of which cannot be found anywhere else in the world. The site is now designated as a national natural monument under the name of “Arareishi Production area of Matsushiro Mine” (currently closed and inaccessible).